I took the above photo a few days ago and when I reread the passage from Dahui's Shobogenzo below, it came to mind as the "just right" companion.
The master who gave the talk below, Fojian, is a 21st generation teacher in China (50th since the Buddha) in the Rinzai/Linji branch of One School Zen.
 Master Fojian said to an assembly,
A monk asked Zhaozhou, “What is the meaning of not moving?”
Zhaozhou depicted flowing water with his hands. The monk had an insight.
Also, a monk asked Fayan, “When one does not grasp appearances, suchness as is does not move. How does one not grasp appearances and see the unmoving?”
Fayan said, “The sun rises in the east, and at night sets in the west.”
That monk also had an insight.
If you can see here, then you will know “the whirlwind flattening mountains is fundamentally always still; the rivers pouring furiously basically do not flow.”
If you cannot, you will not escape the sky turning to the left and the earth turning to the right by too much talk—since of old, and from now, how many times has it happened? The sun flies, the moon runs—no sooner do they rise over the ocean than they set behind the green mountains. The waves of the rivers go on and on, right into the sea, flowing day and night.
[Raising his voice:] Zen worthies, do you see suchness as is?